United States vs China: population
How United States and China compare in population today and out to 2100, side by side, from UN World Population Prospects 2024.
United States and China population, 2000-2100
Population 2000-2100
Side by side
| 🇺🇸 United States | 🇨🇳 China | |
|---|---|---|
| Population today | 348 million | 1.41 billion |
| Population 2050 | 380 million | 1.27 billion |
| Population 2100 | 421 million | 639 million |
| World rank | #3 | #2 |
| Peak year | 2100 | 2021 |
| Median age (2024) | 38 | 40 |
| Fertility rate (2024) | 1.62 | 1.01 |
| Life expectancy (2024) | 79 yrs | 78 yrs |
| Density (per km²) | 38 | 147 |
Why this comparison matters
Behind this comparison sits a larger question about national power. China's population has begun to shrink and age rapidly, while the United States, alone among the big rich economies, keeps growing through immigration. Demographers increasingly read it as a structural advantage for the US over the century, even though China remains far larger in absolute numbers throughout.
United States vs China, explained
Today China is the larger of the two, with about 1.41 billion people against United States's 348 million. United States is the world's 3rd most populous country and China the 2nd.
Their paths to 2100 differ. United States keeps growing over the century, moving from about 344 million to 421 million (+22.2%). China falls sharply, going from 1.42 billion to 639 million (-55.1%).
The order does not flip this century: China is still the larger of the two in 2100. The two trajectories run in parallel rather than crossing.
The deeper contrast is age and fertility. United States has a median age near 38 and 1.62 births per woman, against China's 40 and 1.01. All figures follow the UN's medium-variant projection.